EthCC 2: Clément Lesaege

so hi everyone so today we're going to speak about list curation with dodges and tokens so list creation is everywhere in a web 2 but mostly handled by centralized parties if you want to if you want to set up a platform to sell goods you need to create uh the good to display you need to verify that they are in the right category you need to verify that they are not offensive that they are not illegal you don't want to send a drug on your centralized marketplace forum post a forum post is basically an item in a created list of texts which are not violating the rule of this forum and it's dealt with generally centralized moderator when we go to uh web 3 when we don't have any centralized operator to our system we still need to deal with content curation and because we won't be able to deal it with it with moderator we'll deal with it with crypto economics so we want to make a list of the dodges of image of this dodge meme we can let anyone add an item to this list by putting a deposit so alice she meets a dodge bob look at the image that's fine nothing happened so the item is accepted and alice gets back our deposit but now if alice tries to sorry if if alice tries to submit an image of a cat bob can notice it's a cat put a deposit to to challenge his cat and then it goes through a dispute resolution system is this resolution system rule it's an invalid image alice loses our deposit bob gets a reward and his deposit back and a part of the deposit is used to process the dispute in the dispute resolution system so dispute translation system can be everything it can be one centralized party it can be a multisig or in the case of kleros it's a dao so it's a dao with randomly drawn juror the first problem when we draw people randomly is that you can have someone registering thousands of times to get thousand chance of being drawn and getting most of the votes in the system so we cannot draw people because we don't have an efficient way to verify unicity of people in the system so we can draw tokens so here you have a c e and g drawn as jar and they're going to be able to cast a vote and get paid arbitration fees we now have a second pro second problem which is all to make people vote honestly so if we don't if we just pay a drawer when they make a when they cast a vote they could just put a bot voting randomly or take bribe they would not need to look at images and they would not need to spend cognitive resource to give rollings so to avoid that we use some shelling current mechanism where if you vote coherently with the other juror you win tokens but if you don't you lose tokens so here the juror on the top voted against bob what is that the dodgy mage was valid so they won a few pnk while the two on the bottom they lost a few pnk for being incoherent so even if you're honest once in a while you're gonna lose some token but overall if you're dishonest or voting randomly you're gonna lose way more token than if you are effectively looking at cases and giving inform rolling so that is this chaining called mechanism so i let you all think about what number you want to pick and your goal is to pick the same number as a majority so think about your number okay no people who saw about one thousand please raise your hand okay people who about to know their number please raise your hand so we it seems that we have around sixty percent of people one thousand and forty percent of people giving all the number so you could have all won by saying 3785 um but 1000 was standing out so in the case of a cleros and the shelling coin system what stands out is the truth is honest ruling even if we don't have the label it will seem that the payout matrix is completely symmetric that all the options are similar but when you get the ruling you know that if alice put a picture of a dodge you should vote for alice because the other people are gonna think that you're gonna vote for alice uh and they're gonna think that the other are gonna think that the others are gonna think that they're gonna vote for alice in practice people do that up to three level of reasoning so to test all of that with a low stake we created a dodging trial which is a crypto economic experiment we gave a few dodge coins to people submitting dodge and we gave some yeast to people submitting cats getting accepted to incentivize people to try to attack the system we got more than 1000 images most of them were dodged pictures we got one or two hundred of a picture challenge most of the time picture which was a picture which went to dispute resolution were not picture of dodges even if the majority were a picture of dodges because challenger they do they do their work first and they most of the time only challenge picture of dodges or pictures which can be a bit fuzzy so even when you don't use the display resolution system the simple fear of the dispute resolution system is helping you to make the user behave in an honest manner so you can see example of image we made up into the list and you see that there are all dodges here you can see a few images we did not make it into the list mostly because it was cats trying to get the reward for putting cats so what did people do so people started with quite naive bribes where they promised bribe by adding text to the image so we got tristan and he promised 0.3 is but he just made a promise on the image so no one trusted him and even was in his head he had someone who was not even a juror asking the bribe to be paid and trying to scam the attacker so that was quite fun we then got slightly more advanced images where they were linking to an address showing they had the phone but still no proof that they would be paying effectively to bribe but that would be just because it was a basic attack you can do way better attack because you are on the blockchain you can make smart contract and if you're a malicious party you can make a smart contract which are going to guarantee the jurors that they're going to pay the bribe if they vote for what you want them to vote so that seems to be quite dangerous and even more dangerous is the p perception attack which is very dangerous at least in theory because it has zero cost like if it succeeds the attacker do not even need to pay any bribe so the principle is you want the draw to vote for y so you say okay if you vote for y in the majority vote for y you get y which is the reward in the system so you're good for it but now if you vote for y and the majority votes for x i give you p plus epsilon so a slight amount large so slightly more than p so now as a juror you can see okay if the majority votes for x and i vote for x i get p but if i vote for y i get p plus epsilon so it's better to vote for y now if the majority votes for y and i vote for x i get zero but if i vote for y i get p so i should vote for y and then everyone votes for y and then y is the majority and the briber uh get his result without paying anything because people get paid by in-system incentive so from a surgical perspective that was quite scary for us so that's why even if none were organic we made a publicity attack ourself with smart contracts enforcing those bribes so they were way more efficient than the knife bribes but still not efficient to turn rolling the opposite way i think at work we got perhaps one third of the juror accepting bribes uh but most of the draw even when given a bribe that they would have been certain to get if they try the smart contract choose not to take the bribe so we can ask why do people don't don't take this bribe even if in that it would be economic interest so one reason is that it has a high connective cost because you need to understand that this bribe works you need to verify the smart contract and that can take you a lot of time and you value your time one other reason which was sometimes explained by people who answered us was that they value honesty so if at the end of the day you get few more cents by being dishonest you may not be happier than if you were honest slightly less sense but you have a better vision of yourself you have a better self-esteem because you take a decision which are aligned to what you think it's also about token economics we also had people who claim oh no i'm not going to take bribe even if i could get money from it because if i take bribe i'm going to weaken the system if i weaken the system i we can close i weaken the value of my tokens and so i will weaken my own economic value in the long term so i think here it's a quite interesting way where token are useful to align the incentive because here the token value is linked to all people with a token behave so if you behave in a bad manner you impact the value of your own holding but even if it may not be rational for one individual because they make it more bribed than what their token value uh would be impacted it can still create some kind of group effect where they are part of this token or like this crypto this project and choose not to attack the project they're part of other interesting cases uh we got dodges in the venetian sense so leonardo is the most famous dodge of venice and it was first meeted and juror rejected it but then submitted with the label all the jurors accepted leonardo into the list so that's quite interesting because we can see that either that juror got evidence so the link to leonardo they could type that on google and verify that leonardo is a dodge in the venetian sense so either they got extra information so they then concluded it was a dodge or perhaps more interesting they knew it was a dodge from the beginning but they voted no because they thought that the other people would not think that it was a dodge so it's also important because if you don't have enough evidence the juror may underestimate the capacity of all the jurors and give wrong ruling even if they know that what the honest ruling should be this is still kind of fuzzy because other dodgy the less famous got still still got projected yeah so sexually explicit content that's something really naturally expected but if you do a tcr put a rule to avoid sexually explicit content and even if it is a sexually explicit image were in theory okay and part of a dodge image they were rejected by the juror that's also interesting because we saw that the draw ruled on the spirit of the question and not on the wall toward of the question and that's some kind of debate which could slightly be linked to the diy debate with people well no that's that's the question you should answer the question and no that's obviously not what they meant so you should reject those images we also saw some emergence of caselo uh with an image of dodge of dogs with dodge features but not the right color where at first they tend to be accepted rejected accepted and then they tend to be accepted all the time so we saw that draw look at previous cases to make the decision in the future we also saw that they detected the maliciousness because images with cats and dodge either because both of them or because they speak the dodge way and feel dodge were rejected because they were obviously made to try to get the reward of putting a cat even if the reward policy would not give reward for her image with both cat and dodges that may have confused some people and if you see pictures of dodgies which are other animals they got accepted but dodges and cats did not get accepted this image is quite interesting not really from cryptograms perspective but just from fan like what is that what is that no it's a cat so it's so it just accepts it because no one challenge it and the guy had to give us the other no another angle of the image to convince us but actually a cat so yeah at some point if even human cannot determine it uh that it's uh that this image led it or not no crypto economic mechanism will be able to give you the right result so the only image which was which obviously passed around the cryptocurrency mechanism was this image which got accepted because it never got challenged so all the images with challenges of of cats were rejected but this one was just never challenged and we cannot really have something which is 100 secure because if the system always reject a item that should not belong to the system people are going to stop post malicious items and if people stop posting malicious item people will stop checking for malicious items and if people stop checking for malicious item then people can post malicious items so you can see this matrix of of payouts and you can see that none of the pure strategy leads to an equilibrium because if no one does anything you shouldn't commit crime if you commit crime and you get verified you should not have committed crime in the first place and if you verify and there are no crime you should not have verified because you should not have spent your cognitive resources uh verifying so that's the simplification of these two parties in practice you have multiple posters and multiple verifiers like crypto police so we're gonna always end up into a mixed natural equilibrium we're gonna we're gonna have a part of images which are gonna be accepted even if there are wrong images and then you can tune parameters to determine what ratio is acceptable depending uh and also taking the cost into account let the no crime no police crime police police crime we got some quite interesting feedback about the world experiment about notion of truth so some people already got into it and we even got some people doing some machine learning using the dodge and trial data set and concluded that they will probably be able to make sure to make ai jurors so okay those are fun but that's an experiment now let's go to something perhaps slightly more impactful on the ecosystem even if i really like dodges which are token token treated registries so using crypto economic mechanisms similar we can make a list of tokens because current lists of tokens tend to be made by centralized party this quite often gets them wrong as you see if you look at the pnk you see most of them are fake token meant to scam people they managed to scam for about 500 worth of fake token we can see that on parity we had people putting tokens which were giving balance to everyone in the world so showing in everyone wallet like sim and for some even being uh even having offensive images if you look at uni swap they put some token at first but no nothing is modified because it's a decentralized exchange uh and you need to be able to update uh token and add new token to those decentralized product either centrally but you have a problem or buy a cryptocurrency mechanism so that's why we made this token token created registry with similar incentive so alice puts the token gets accepted she puts another token it gets accepted so at the first level we just verify that the token name address ticker and symbol are matching so you can even submit scam at this point but then what we can add is a badges so we can have a badge stating that this token decentraland is satisfying some criterion for an exchange and it's going to be added but if you try to add it to a token which is a scam you will get like a challenge and with similar mechanism you prevent this token from getting badges so this is all the new listing system of ethenex is going to work where you they will pull data from this token token created list and then select randomly some of them to be voted by their community so the final vote is still on the community but using this registry is a way to filter most of the token which are not interesting to put to vote so you can see a few screenshots of this token token created registry which is going to be live on mainly tomorrow tokens adding uh submitting a token badges and the new jira front where they can where drawer can rule whether the information is correct or not so thanks everyone and we're going to go to the question [Applause] any questions hey it's on i wonder what role lawyers might play in the system a lawyer do you have provision to have a lawyer in the process to make a case for any one side of an argument oh no you don't need any lawyer anyone can challenge listing that they believe are incorrect not not necessarily just for this but in general in the the cleros value proposition if i have a complex case that's not so black and white how am i going to present that to the jurors so currently i've never seen anyone using something which would look like a lawyer service but there is nothing which will prevent people from paying people to present the case in a good manner give interesting evidence and you could even make smart contract such that you pay this lawyer and this lawyer get paid only if you win the case you can make a smart contract for that that's not something which has been done but that's something which could have been done yeah cool thank you uh thank you very much very interesting uh talk um what do you think's the reason for that one image to pass through and not being challenged the one with the shark and the cat what do you think was the reason that it just went through so it's after at the beginning we got a lot of uh meter and a lot of people looking at the list and challenging malicious images but after some point people kind of gave up like seeing that they did not manage to put any cat in it because you need to put a deposit so they were losing real ease by putting fake images so at some point people look oh we have like 100 pictures of cars they all got rejected i'm not gonna try my luck so they stop posting these images and then if there is no images anymore that's not interesting to look at the list to get the reward because you get to reward only when you challenge a malicious picture and you win your dispute but if there is no malicious picture you have nothing to win so you have this kind of like crypto police problem because the crypto police is not uh paid the fixed fees they are just uh paid uh bounties when they manage to find out malicious items uh and if there is no crime there is no police and then if there is no police there is no crime oh there is crime again sorry thank you so what's the source of randomness for drawing jurors and how does that protect from let's say having a 51 attack or whatever else with someone accumulates a lot of the a lot of tokens so on the source of randomness it's currently using a block hash blockage is not a perfect source of randomness but it cannot be completely set to a particular value so this means that if you're a miner and you mine a block which lead to random number you don't like you can choose not to publish this block wave the black reward the wave the fees to basically reroll the dice you also have cases when you have two when you have heads of similar lengths such that as a miner you can choose on which one to build and in this case you have the choice between two random numbers so that's the two problem with uh with black hash but all of them can only allow you to reward the dice extraordinarily or at a high cost but they can never allow you to fix it to a particular value so even if you can reroll the dice unless you have almost the majority you won't manage to get the majority of the gerald runs so that was on the randomness and on the randomness it will also be moved to a verifiable delay function when those verifiable delay bacon will be finished but one that's still under heavy research by the srm foundation and on the 15 percent attack one of the major protection against fisherman's attack is that if you view a person attack you break the system so you break cleros you break the value of your token because if you're 15 attack you have to have 50 of the tokens so that has a really high cost uh to you to do this 15 percent attack because on this case that's the situation if it gets attack people are going to stop using it or they're going to switch to a clone of the system which are not attacked and the honest minority can force the system into a nuclear host removing the stake of all the dns attacker to make a new court which is uh honest so you can attack it with similar security assumption like srm proof of stake like you can buy 15 of the e-state and attack ethereum but if you do so you're going to destroy the value of all your ease and you're going to have a fork and that's going to probably not be economically interesting for you to do so so similar similar protection as proof stake thank you [Applause]